Generates c# source code that cannot be compiled.

### What are you generating using Kiota, clients or plugins?

API Client/SDK

### In what context or format are you using Kiota?

Nuget tool

### Client library/SDK language

Csharp

### Describe the bug

Given the following shortened API spec:

```yaml
openapi: 3.0.4
info:
  title: Process Parameter API
  version: 1.0.0

servers:
  - url: https://{ServerHost}
    variables:
      ServerHost:
        description: Host name and port of the server.
        default: localhost:9006

paths:
  /process-parameters:
    post:
      summary: Create a new process parameter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ProcessParameter'
      responses:
        '201':
          description: Created
        '400':
          description: Bad Request

components:
  schemas:

    ProcessParameter:
      type: object
      description: Defines a single process parameter.
      properties:
        allowed_values:
          description: List of allowed values in case it's a numeric or string process parameter.
          nullable: true
          oneOf:
            - type: array
              items:
                type: number
            - type: array
              items:
                type: string
        key:
          type: string
          description: Key of the process parameter (acts as identifier).
          maxLength: 256
        station_id:
          type: string
          description: The id of the station the process parameter belongs to.
        kind:
          type: string
          enum: [BOOLEAN, NUMBER, STRING]
      required:
        - key
        - station_id
        - type
      example:
        key: /ST01/23992/VIBRATE
        station_id: ST01
        kind: BOOLEAN
```

```bash
C:\dev\Issue1
❯ kiota generate -l CSharp -c Client -n Issue1.Client -d ./OpenAPI-spec.yml -o ./Client
Generation completed successfully
Client base url set to https://{ServerHost}
```

Kiota generates source code that can not be compiled:

```bash
C:\dev\issue-1 via .NET v9.0.300 🎯 net9.0
❯ DOTNET_CLI_UI_LANGUAGE=en dotnet build
Restore complete (0,3s)
  issue-1 failed with 2 error(s) (0,2s)
    C:\dev\issue-1\Client\Models\ProcessParameter.cs(120,85): error CS8121: An expression of type 'List<double?>' cannot be handled by a pattern of type 'List<double>'.
    C:\dev\issue-1\Client\Models\ProcessParameter.cs(122,37): error CS0029: Cannot implicitly convert type 'System.Collections.Generic.List<double>' to 'System.Collections.Generic.List<double?>'

Build failed with 2 error(s) in 0,7s
```

Problematic code:
```csharp
/// <summary>
/// Creates a new instance of the appropriate class based on discriminator value
/// </summary>
/// <returns>A <see cref="global::Issue1.Client.Models.ProcessParameter.ProcessParameter_allowed_values"/></returns>
/// <param name="parseNode">The parse node to use to read the discriminator value and create the object</param>
public static global::Issue1.Client.Models.ProcessParameter.ProcessParameter_allowed_values CreateFromDiscriminatorValue(IParseNode parseNode)
{
	_ = parseNode ?? throw new ArgumentNullException(nameof(parseNode));
	var mappingValue = parseNode.GetChildNode("")?.GetStringValue();
	var result = new global::Issue1.Client.Models.ProcessParameter.ProcessParameter_allowed_values();
	if(parseNode.GetCollectionOfPrimitiveValues<double?>()?.AsList() is List<double> doubleValue)
	{
		result.Double = doubleValue;
	}
	else if(parseNode.GetCollectionOfPrimitiveValues<string>()?.AsList() is List<string> stringValue)
	{
		result.String = stringValue;
	}
	return result;
}
```


### Expected behavior

Source code does compile by eg. producing:

```csharp
if(parseNode.GetCollectionOfPrimitiveValues<double?>()?.AsList() is List<double?> doubleValue)
```
instead of:

```csharp
if(parseNode.GetCollectionOfPrimitiveValues<double?>()?.AsList() is List<double> doubleValue)
```

### How to reproduce

```bash
mkdir Issue1
cd Issue1
dotnet new console
# store API spec as OpenAPI-spec.yml
kiota generate -l CSharp -c Client -n Issue1.Client -d ./OpenAPI-spec.yml -o ./Client
dotnet add package Microsoft.Kiota.Bundle
dotnet build
```

### Open API description file

```yaml
openapi: 3.0.4
info:
  title: Process Parameter API
  version: 1.0.0

servers:
  - url: https://{ServerHost}
    variables:
      ServerHost:
        description: Host name and port of the server.
        default: localhost:9006

paths:
  /process-parameters:
    post:
      summary: Create a new process parameter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ProcessParameter'
      responses:
        '201':
          description: Created
        '400':
          description: Bad Request

components:
  schemas:

    ProcessParameter:
      type: object
      description: Defines a single process parameter.
      properties:
        allowed_values:
          description: List of allowed values in case it's a numeric or string process parameter.
          nullable: true
          oneOf:
            - type: array
              items:
                type: number
            - type: array
              items:
                type: string
        key:
          type: string
          description: Key of the process parameter (acts as identifier).
          maxLength: 256
        station_id:
          type: string
          description: The id of the station the process parameter belongs to.
        kind:
          type: string
          enum: [BOOLEAN, NUMBER, STRING]
      required:
        - key
        - station_id
        - type
      example:
        key: /ST01/23992/VIBRATE
        station_id: ST01
        kind: BOOLEAN
```

### Kiota Version

1.26.1+a5df7c03bab621bb2d4dc728516fc9c488cabadb

### Latest Kiota version known to work for scenario above?(Not required)

_No response_

### Known Workarounds

_No response_

### Configuration

- Windows 10
- x64
- no

### Debug output

<details><summary>Click to expand log</summary>
```bash


C:\dev\Issue1 via .NET v9.0.300 🎯 net9.0
❯ kiota update --ll debug --clean-output --output .
info: Kiota.Builder.KiotaBuilder[0]
      Cleaning output directory C:\dev\Issue1\.\Client
dbug: Kiota.Builder.KiotaBuilder[0]
      kiota version 1.26.1
info: Kiota.Builder.KiotaBuilder[0]
      loaded description from local source
dbug: Kiota.Builder.KiotaBuilder[0]
      step 1 - reading the stream - took 00:00:00.0055954
dbug: Kiota.Builder.KiotaBuilder[0]
      step 2 - parsing the document - took 00:00:00.0660983
dbug: Kiota.Builder.KiotaBuilder[0]
      step 3 - updating generation configuration from kiota extension - took 00:00:00.0000773
dbug: Kiota.Builder.KiotaBuilder[0]
      step 4 - filtering API paths with patterns - took 00:00:00.0036079
info: Kiota.Builder.KiotaBuilder[0]
      Client root URL set to https://{ServerHost}
dbug: Kiota.Builder.KiotaBuilder[0]
      step 5 - checking whether the output should be updated - took 00:00:00.0115690
dbug: Kiota.Builder.KiotaBuilder[0]
      step 6 - create uri space - took 00:00:00.0022967
dbug: Kiota.Builder.KiotaBuilder[0]
      InitializeInheritanceIndex 00:00:00.0022914
dbug: Kiota.Builder.KiotaBuilder[0]
      CreateRequestBuilderClass 00:00:00
dbug: Kiota.Builder.KiotaBuilder[0]
      MapTypeDefinitions 00:00:00.0040606
dbug: Kiota.Builder.KiotaBuilder[0]
      TrimInheritedModels 00:00:00
dbug: Kiota.Builder.KiotaBuilder[0]
      CleanUpInternalState 00:00:00
dbug: Kiota.Builder.KiotaBuilder[0]
      step 7 - create source model - took 00:00:00.0514567
dbug: Kiota.Builder.KiotaBuilder[0]
      16ms: Language refinement applied
dbug: Kiota.Builder.KiotaBuilder[0]
      step 8 - refine by language - took 00:00:00.0169586
dbug: Kiota.Builder.KiotaBuilder[0]
      step 9 - writing files - took 00:00:00.0262235
info: Kiota.Builder.KiotaBuilder[0]
      loaded description from local source
dbug: Kiota.Builder.KiotaBuilder[0]
      step 10 - writing lock file - took 00:00:00.0068137
Update of Client client for CSharp at C:\dev\Issue1\.\Client completed
Client base url set to https://{ServerHost}
Update of 1 clients completed successfully

```
</details>


### Other information

❯ dotnet --version
9.0.300

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Generates c# source code that cannot be compiled. #6635

What are you generating using Kiota, clients or plugins?

In what context or format are you using Kiota?

Client library/SDK language

Describe the bug

Expected behavior

How to reproduce

Open API description file

Kiota Version

Latest Kiota version known to work for scenario above?(Not required)

Known Workarounds

Configuration

Debug output

Metadata

Assignees

Labels

Type

Projects

Milestone

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Development

Generates c# source code that cannot be compiled. #6635

Description

What are you generating using Kiota, clients or plugins?

In what context or format are you using Kiota?

Client library/SDK language

Describe the bug

Expected behavior

How to reproduce

Open API description file

Kiota Version

Latest Kiota version known to work for scenario above?(Not required)

Known Workarounds

Configuration

Debug output

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions